Anticancer therapy by transplanting vascular endothelial progenitor cells

Abstract

An anticancer therapy using autologous cells or the like, which induces the regression of cancer or has favorable drug delivery effects and brings about reduction or withdrawal of a hypoxic region(s) in tumor is provided. Transplantation of endothelial progenitor cells, via intravenously or other methods leads to tumor growth inhibition, an increase of the vascular density with an enlargement of the vascular diameter, and reduction of a hypoxic region(s) in the tumor. Allogeneic transplantation of endothelial progenitor cells may be achieved to secure the cells for the therapy, however, autologous transplantation of endothelial progenitor cells from cancer patients would be desirable to evade rejection. When autologous cells are used, mononuclear cells are separated from the peripheral blood or bone marrow of the patient and cultured using an endothelial differentiation medium containing cytokines such as VEGF to obtain adherent cells, which can then be collected and used as endothelial progenitor cells.

The invention claimed is: 
     
       1. A method for treating a tumor, comprising administering a composition consisting essentially of endothelial progenitor cells to a mammal, wherein the endothelial progenitor cells are adherent, are obtained from mammalian peripheral blood, bone marrow, or cord blood, and are capable of uptake of acetylated LDL and binding a lectin, and further wherein the endothelial progenitor cells have not been subjected to genetic engineering. 
     
     
       2. The method of  claim 1 , wherein the administered endothelial progenitor cells inhibit growth of the tumor. 
     
     
       3. The method of  claim 1 , wherein the administered endothelial progenitor cells reduce a hypoxic region(s) in the tumor. 
     
     
       4. The method of  claim 1 , wherein the administered endothelial progenitor cells induce remodeling of vessels of the tumor. 
     
     
       5. The method of  claim 1 , wherein the endothelial progenitor cells are administered transvenously. 
     
     
       6. The method of  claim 1 , wherein the tumor is selected from the group consisting of pancreatic cancer, esophagus cancer, gastric cancer, lung cancer, kidney cancer, thyroid cancer, parotid cancer, head and neck cancer, bone and soft tissue sarcoma, ureter cancer, bladder cancer, uterine cancer, liver cancer, breast cancer, ovarian cancer, and uterine tube cancer. 
     
     
       7. The method of  claim 1 , wherein the tumor is pancreatic cancer. 
     
     
       8. The method of  claim 1  further comprising administering an anticancer agent(s) to the mammal, wherein activity of said anticancer agent(s) is enhanced by the administered endothelial progenitor cells. 
     
     
       9. The method of  claim 1  which is combined with radiotherapy, wherein said radiotherapy has an effect that is enhanced by the administered endothelial progenitor cells. 
     
     
       10. The method of  claim 1 , wherein the lectin is FITC-lectin or  Ulex europaeus agglutinin lectin.